A Researcher Has Grown Monolayers of Cells from Either of Two

Short Answer

A researcher has grown monolayers of cells from either of two epithelial cell lines on a permeable supporting membrane that separates two electrolyte chambers. One of the cell lines (A) has been derived from the mammalian kidney and forms epithelial sheets resembling those lining the renal collecting duct and the urinary bladder. The other (B) is derived from the mammalian small intestine. The researcher has measured the voltage (V) and electrical current (I) across the monolayer and has plotted the results in the graph below. Which line (1 or 2) in the graph do you think corresponds to cell line A? Recall that current (I) is related to the applied voltage (V) by the equation I = V/R, in which R is the electrical resistance. Write down 1 or 2 as your answer.